/Engine/Source/Runtime/Experimental/Chaos/Public/Chaos/TriangleMesh.h
Note that this data is lazily calculated with the SegmentMesh (this method is not threadsafe unless it is known that the SegmentMesh is already up to date)  A map from all edge indices, to the indices of their containing faces.
const [TArray](API\Runtime\Core\Containers\TArray)< [TVec2](API\Runtime\ChaosCore\Chaos\TVec2)< int32 > > & GetEdgeToFaces() const